Lubricating oil



Patentgd Aug. 3, i937 l Q UNITED STATESPATENT ornc 1 Ferdinand W. Broth, Petrolia, Pa, assignor, by mesne assiznments, to Standard Oil Development Company No Drawing. Application October 2, 1934, Serial No. 746,509

This inventionrelates to improved lubricating treated materials may be added as such; .or the oils, and especially to improved lubricating oils modified material may be separated from theunfiled February 17, 1932. modified material in any batch of oil treated is The invention is applicable to the reduction of apparently small and can be concentrated by r the pour point of alubricating oil, and especialmeans of vacuum distillation, as a large part'of ly to a petroleum lubricating oil containing in the unmodified material may be removed from solution, parailln, or substances of a waxy nature, the admixture with the modified material be- 10 such as stearic acid. Such materials may occur cause of its relatively lower boiling, point, but

mally have a tendency to precipitate when the oil not isolated and the distillation residuemay still is cooled, thereby causing th oil to set or gel contain a substantial amount of inactive portion,

and causing the oil to flow sluggishly or not at Among the various uses to which this modified oil l5 source whatever. are wax free, for the purpose of increasing the oili 20 tion of a modified oil by application of an elec- 011 so prepared is added to the lubricating oil 25 relatively long principally/straight hydrocarbon rial added is sufficient to reduce the pour point to chains, of, for example, 10 or 12 carbon atoms or within satisfactory limits. In the preferred apmore, plication of my process, the modified oil is added The modification or polymerization of these 7 to a lubricating oil derived from" any waxyj oil materials, by subjecting the same to an electrical such as, for example; Pennsylvania crude oil tion. The-method'is described in German Patent temperature curve but not infrequently manifest No. 234,543, issued May 13, 1911; and is described an unsatisfactory pour point. The application in various articles, appearing in the literature as of the modified material hereinabove described to 40 the Voltol process. i such oil, and particularly in the amounts requisite 9 The polymers which I desire to form have a to effect the desired modification of pour point, is

molecular weight in excess 01' 600, and up to 2000 believed to be entirely novel and constitutes the extremely difficult to separate fractions closely as winter oils, and the modified materialcan be 43 and to state exactly at just what point this-pour usedwith such oils with excellent results, greatly inhibiting action begins.- reducing their pour point without excessive in- At least a portion of the oil subjected to treatcreaseof viscosity. In carrying out my process I ent is modified to compounds of higher molecumay, for example, addsufficient modified mate- ;0 lar weight and viscosity than the oil treated. The rial of suflicient potency to test of 85 F. or higher to reduce the pour test to 10 F. or lower.

As previously stated, the invention is applicable only to those oils containing paraiiin or waxy substances in liquid solution which manifest a tendency to gel or set on cooling due to the precipitation of the paraiiin or waxy materials.

The amount of the modifled oil to be added to the waxy lubricating oils depends on many tactors and it is best determined by simple routine test on the particular samples of modified oil and waxy lubricating oil.

similar treatment give products decidedly difierent potency and vdiilerent oils show different degrees of susceptibility to the same depressor. For example, it is generally necessary to add more of the given depressor to a more viscous oil than to a less viscous oil to obtain an' equivalent Even oils of the same viscosity but derived irom diiierent sources or finished by diilerent methods showdiiierent susceptibilities. The current density, frequency and voltage of the electrical discharge may also influence the modification.

Furthermore, tainfoi theheavier as indicated above, it is only ceriractions oi the modified oil which possess the pour depressing property, and these particular fractions cannot be isolated so that it is extremely diiiicult to speciiy exactly the amount of the active materialadded. If the oil is subjected to the voitolization treatment for several hours, the content of the active sub stance is quite small and naturally a larger proportion of the whole ing chamber would have to be added than in the case where more completely voltolized material, for example, one treated tor several days, is used. Generally voltolization is carried out as long as possible Just avoiding the precipitation of insoluble or gummy materials. and where a material is so prepared and added to the oil in tow the amount may vary from. it to or more, but it a concentrated product, tor example, the residue obtained by vacuum distillation, be used it is sumcient to add considerably less, for example. from .2 to 3%. Under such conditions eventhoughtheinhibitoritseiiisaveryviscous product it may be med in such amounts as not toincreasetheviscodtyoitheoiitowhichitis added by any substantial amount. For example, ordinarilytheincreascmaybeiromlto2or3seconds Bayboit at 210' l"., or may be limited to, say, an increase of [seconds or seconds at 10W which has a viscosity of 5,000 to 10,000 sec. Baybolt at 0' 1". and 00 to 115 sec. Saybolt at t to obtain a large minimum viscosity general. therefore, it may be said that the amount at thepour inhibitor to be added depends on various iactors. In general it will fall between thelimita o! {e and 5% or even 10% more or less, and the moat elective amount for in hand may be determined by routine test. ular oil and the Two diilercnt types It has been found, for example, that different starting materials under product from thevoltolizhold the parailin making up samples oi the partiO- depressor. oivoitol. diilering onlyin.

the relative proportions of mineral oil to vegetable oil, were obtained irom the raw material by electrical treatment; one a Belgian voltol sold under the trade name of Electrion" and a second, German voltol, designated End voltol". The physical characteristics of these two products, are as follows:-

Eicctrion End voitol .Gravity at 60 F. 23.1 A. P. I 18.3 A. P. 1. Via. Saybolt 210 733sec 975 sec. Poul-test 40F Flash point 410 F- Fire point 465 F F. Color (Lovibond yellow 5 red 20 yellow 14 red.

36 in. eel Acidity 0.63 mg. KOH Alkalinity. 0.47 Iodine value 35.2.... 17.8. Sagoniiication No- 74.7 10.0.

The following examples illustrate thezeifects oi small amounts of End voltol upon a Pennsylvania waxy lubricating oil having the following properties:-

Specific gravity at 60 F.; 28.0-A. P. I. Viscosity (Say) at 210 F '79 sec. Flash point 450 F.

Fire point; 515 F. Pour point F.

Color (Lovibond in. cells)--- 20 yellow 38 red.

Upon the addition of 6.5% crane voltol, the following mixture was obtained:-

Specific gravity at 60" r' 28.0 a. P. I.

Viscosity (Say) at 210 F 80 sec. 7 Flash point 450 F. Fire point 515 F. Pour point 10 F.

Color (hovibond in. cells)'..... 20 yellow as red.

Upon the addition- 0! 1.0% or End voltol, the following mixture was obtained:-

Specific gravity at 60 F 273 A. P. I. Viscosity (Say) at 210 F 82 sec. Flash point 445 F. Fire point 505 F. Pour point "..I -7 F Color (LovibondV, in. cells)". 20 yellow as red.

From the above, it can be seen that the physical properties of thelubricating oil and the lubricating oil-voltol mixture are substantially the same, with the exception 0! the pour point, which is appreciably lower in the mixture.

I believe the effect in waxy oils to be due to the fact that as sOOn. as microscopic crystals of paraflln are formed by. cooling, the modified material is adsorbed on the surface 01' the crystals,-

thereby operating to inhibit the formation of large crystals which would'seriously affect the pour point of theoil and thereby ,operating to in a state of colloidal suspension. 1 do not wish however, to be'limited by this statement of theory; but only by the appended claims wherein I have endeavored to claim broadly a lubricating oil containing voltol in amount and potency adapted to lower the normal pour point of the lubricating oil.

. By the term voltol" as used in the claims, I mean a product obtained by subjecting a normaiiy liquid oil to an electrical silent discharge,

:whereby a substantial-degree oi polymerization I claim:--

1. A lubricating oil composition substantially point or said lubricating oil at least 10' F. without substantial change in the viscosity of said oil.

w. 31mm 

